A handful of tests are proving flakey, which are greatly increasing our time to run tests (especially with the cache issues we are seeing).

1. Google\ApiCore\Tests\Unit\Middleware\RetryMiddlewareTest::testCustomRetryRespectsTimeout - Failed asserting that 3 matches expected 2.
2. Google\ApiCore\Tests\Unit\Middleware\RetryMiddlewareTest::testRetryLogicalTimeout - Failed asserting that false is true.